[Rhodes22-list] What's The Difference Between #1, #2, #3, ... ,
#6 Fuel Oil?
Rik Sandberg
sanderico at earthlink.net
Wed Dec 10 09:19:14 EST 2003
Roger,
Excellent desciption of diesels and why/how they work. Far better than I
could have done.
The most important point in Rogers post concerning winter operations with
diesels is when he talks about the cloud point. This is what what most people
think of as the point where diesel fuel "gells" I doubt that one could see
this in their cars of SUVs. In a truck though, you can easily see into the
fuel tanks and when your fuel is cold enough to be at the cloud point, it is
readily visible. You will start to see a "waxy" sort of layer floating on to
of the fuel and the fuel below will not appear clear anymore, but cloudy. The
whole idea is top keep the fuel warmed above this cloud point temperature, or
to lower the cloud point temperature by adding chemicals. My experience has
been that not all brands of diesel fuel have the same cloud point
temperature. Or, perhaps this can even vary from one batch to another at the
same station. Also not all cloud point lowering chemical treatments are
created equal, some seem to be better than others.
When you are dirving in extremely cold weather, it becomes much more
difficult to keep your fuel warmed above the cloud point, because the "wind
chill" will remove the heat from your fuel tanks, perhaps faster than it is
being rewarmed by your engine. Diesel engines have what is called a fuel
by-pass. That is, not all of the fuel that is pumped from the tank is
injected into the cylinders and burned. Some of it is bypasses the injector
pump and is returned to the tank. During this round trip, it is warmed. The
secret to the whole thing is to conserve enough of the warmth, or to add even
more with an additional fuel heater, to keep the fuel in the tank above the
cloud point. If you can do this, your diesel will continue to run, no matter
how cold it gets. Fail to do this and you will eventually end up with plugged
fuel filters and a cold walk in your future.
Mostly from the school of hard knox
Rik
On 12/10/2003 08:14 am, you wrote:
> Hi Everybody,
>
> The 1st thing you need to know is that crude oil is a very complex mixture
> of literally thousands of different organic, inorganic, and organo-metallic
> compounds & the specific composition varies greatly between crude oils from
> different fields. One of the first processing steps in an oil refinery is
> to send the crude oil thru a distillation tower. In the distillation
> tower, the components in the crude oil mixture are separated into fractions
> by their boiling point ranges. The components with the lowest boiling
> points come out the top of the distillation tower as vapor. These would
> include compounds like methane, ethane, ethylene, propane, and butane.
> These so called "light components" are sent to another distillation tower
> which operates at cryogenic temperature for further separation. Going down
> the crude oil distillation tower, fractions with greater & greater boiling
> point ranges are removed as liquid side streams. From the top of the tower
> down, these fractions are: gasoline or naphtha, JP-4, kerosene or #1 fuel
> oil, #2 fuel oil, #4 fuel oil, #5 light, #5 heavy, & #6 fuel oil. #3 fuel
> oil is not an official API crude oil fraction designation because it would
> have to be removed from the distillation tower very near the feed port.
> Removal of this #3 fuel oil side stream in the vicinity of the feed port
> would tend to upset the operation of the distillation tower. Believe me,
> achieving stable on-spec operation of a distillation tower with 9 or 10
> product streams & a variable feed stock is one of the most difficult
> process control problems in all of chemical engineering, even without
> screwing up the column operation by removing a side stream near the feed
> port! Sometimes refineries will cut a deal with a local business & sell
> them a product called #3 fuel oil with a boiling point range intermediate
> between #2 fuel oil & #4 fuel oil. But, it's always made by blending #2
> fuel oil & #4 fuel oil. Remember, all these products are not pure
> compounds. They are complex mixtures that meet a boiling point range
> specification.
>
> OK, so what happens if you feed a diesel engine a fuel oil that's too
> light? The fuel injection system in a diesel engine has a number of very
> precisely machined, highly polished components that meter & atomize the
> fuel. These pieces/parts depend upon the lubricating qualities of the fuel
> oil to lubricate & cool them as they operate. A fuel oil that's too light
> will not have the oil film strength (basically viscosity) to prevent
> metal-to-metal contact in the fuel injection system. The fuel injection
> system will self-destruct in short order. In addition, a fuel oil that's
> too light will have a boiling point range outside of the design range of
> the fuel injection system. Remember, the fuel injection system is located
> right next to a hot engine. If the light fuel oil starts vaporizing inside
> the injection pump &/or injectors, the system will stop working. There
> will be instant catastrophic metal-to-metal contact & the system will seize
> up. Finally, smooth operation of the diesel engine depends upon the
> atomized droplets of fuel in the combustion chamber behaving in a
> predictable manner. Basically, what's supposed to happen is that in the
> microseconds immediately following fuel injection, the light components of
> the diesel oil mixture start boiling out of each droplet. These light
> components mix as a vapor with the air in the combustion chamber,
> eventually forming a mixture with a composition within the flammable range.
> Somewhere in this vapor space, the flammable mixture lights off due to the
> adiabatic heat of compression (remember it's a diesel - no spark plugs).
> The flame front rapidly consumes all the fuel present as a vapor & ends up
> burning at the surface of the remaining droplets of fuel. These droplets
> of fuel progressively boil up their remaining lightest components & the
> remaining droplet gets enriched in heavy boiling components. Under heavy
> load, there isn't enough time available during the 4-cycle engine's power
> stroke to completely combust the heaviest components. These heavy
> components get ejected with the exhaust gases & we see them as diesel smoke
> & soot. If there are too much light boiling components in the diesel fuel;
> then, too much of the droplet vaporizes in-between fuel injection &
> ignition. Two things can happen. Ignition can actually occur while the
> fuel injectors are still atomizing fuel. The fuel injectors were not
> designed to have a high temperature flame impinging on them while they are
> in operation atomizing fuel & they can be damaged. The other thing that
> can happen is that a relatively large amount of light boiling components
> end up in the vapor space prior to ignition. When this big fuel charge
> lights off, combustion is too rapid & the
> pressure/temperature in the combustion chamber exceeds design limits. This
> can cause problems like blown head gaskets, holes in pistons, burnt valve
> seats, etc. It's sort of like having the spark timing set incorrectly on a
> gasoline engine &/or using a fuel with too low an octane number for the
> spark ignited engine's compression ratio. In fact, diesel fuels actually
> have a "cetane number", which is the opposite of an "octane number". A
> high cetane number means the fuel will preignite very readily. Diesel
> fuels have a low octane number and a high cetane number. The optimum
> injection timing in a diesel engine strongly depends upon the lag time
> between fuel atomization & initial light off & this lag time is mostly
> controlled by the boiling point range of the diesel fuel.
>
> So what happens if you feed a diesel engine a fuel oil that's too heavy?
> The viscosity of the fuel oil goes up along with the boiling point range.
> A heavy fuel oil may be too viscous for the fuel system to pump from the
> fuel tank to fuel injection metering system, especially at low
> temperatures. In addition, all fuel oils have a specification called the
> "cloud point". Basically that's the temperature at which the fuel oil
> becomes visibly cloudy or scatters transmitted light. Physically, what's
> happening is that the heaviest boiling components in the fuel oil have
> solidified into micron sized particles of a waxy material. Remember all
> those very precise, highly polished pieces/parts in the fuel injection
> system? The diesel engine's fuel system has a system of very fine mesh
> filters & oil/water separators designed to filter out abrasive particles &
> water in order to protect those parts. These waxy particles will clog up
> the fuel filters in a diesel engine very quickly. Winter diesel fuel
> additives increase the solubility of these waxy materials so they stay
> dissolved. The higher viscosity fuel oil may not atomize properly in the
> fuel injectors, resulting in the atomized droplets being too big in the
> combustion chamber. Bigger droplets result in less surface area for the
> light boiling components to evaporate from. In addition, the heavy fuel
> oil has relatively less of the lighter boiling components in it to begin
> with. So, there are less of the low boiling components present to vaporize
> off the droplets & those that are there vaporize more slowly because of the
> bigger droplets to mix with the air in the combustion chamber to light the
> fire. In other words, especially at low temperature, the engine may not
> even run on this fuel. That's why diesel engines have glow plugs
> (combustion chamber preheaters) for winter operation. Even if the diesel
> engine does run on this fuel, a much larger % of the combustion will be of
> the slower, less efficient variety wherein burning occurs at the surface of
> the droplets. I would expect the engine would be down on power & the
> exhaust would be very smoky & sooty.
>
> So, although diesel engines can theoretically burn a wide range of fuels;
> in reality, they are pretty finicky about what they will reliably run on.
>
> There, that's probably much more than you ever wanted to know re fuel oil
> specifications & how diesel engines work. Hopefully, I answered your
> question.
>
> Roger Pihlaja
> S/V Dynamic Equilibrium
>
> ----- Original Message -----
> From: "Kroposki" <kroposki at innova.net>
> To: "'The Rhodes 22 mail list'" <rhodes22-list at rhodes22.org>
> Sent: Tuesday, December 09, 2003 9:31 AM
> Subject: [Rhodes22-list] Michael's Diesel #1 and #2
>
> > Dan, Rik and Rummy,
> > Dan thank you for the latest on Ford's diesels, and for your
> > inputs on diesel fuel and additives.
> > Maybe we can get Roger to explain the chemical differences
> > during the Christmas holidays, if he gets them.
> > As for #3, it was used in big locomotive engines during the
> > transition from coal to diesel. It was used to generate steam.
> > Ed K
> > -----Original Message-----
> > From: rhodes22-list-bounces at rhodes22.org
> > [mailto:rhodes22-list-bounces at rhodes22.org] On Behalf Of Michael Meltzer
> > Sent: Monday, December 08, 2003 11:28 PM
> > To: The Rhodes 22 mail list
> > Subject: Re: [Rhodes22-list] RE: Michael's Diesel #1 and #2
> >
> > thanks, I will watch it and take it easly on the centen booster, BTW
> > mine might be a early one 3/2003(did not know it until I picked
> > it up), is their anything I should watch out for or bitch to the dealer
> > about?(reflash the chip)
> >
> > MJM
> > ----- Original Message -----
> > From: "Dan Bodnar" <dsbodnar at earthlink.net>
> > To: "'The Rhodes 22 mail list'" <rhodes22-list at rhodes22.org>
> > Sent: Monday, December 08, 2003 11:23 PM
> > Subject: RE: [Rhodes22-list] RE: Michael's Diesel #1 and #2
> >
> > > Michael,
> > > I've had several of the old 7.3L Diesels in E350 Vans. The last one I
> >
> > owned
> >
> > > was in 2001 and it had glow plugs and a fuel heater and I'm fairly
> >
> > certain
> >
> > > that the new 6.0L still has the fuel heater. I'm in the Metro Detroit
> >
> > area
> >
> > > and we rarely have nights much colder than -10 degrees. I learned
> >
> > that I
> >
> > > did not need to plug it in unless it was going to be colder than 10
> >
> > below
> >
> > > 'cause the diesel started fine. I did plug it in when I knew it would
> >
> > be
> >
> > > colder than 10 below at night just to be safe. But, having forgotten
> >
> > to do
> >
> > > it a few times, taught me that they would start using just the
> >
> > recommended
> >
> > > start procedure.
> > >
> > > Anyway, fresh winter grade fuel, or some Premium diesel (which I think
> >
> > is
> >
> > > really #1) and your diesel should do fine. Also make sure that the
> >
> > water
> >
> > > separator really does get drained with every oil change. I never had a
> > > diesel not start. They were a little smoky sometimes when it was zero
> >
> > or
> >
> > > colder, but they always started. I only used a diesel fuel
> >
> > conditioner on
> >
> > > one trip into Michigan's Upper Peninsula where I knew I was going to
> >
> > have
> >
> > > 20+ below-zero weather. I don't remember the gel point of diesel
> >
> > either,
> >
> > > but I'm pretty sure it is lower than 15 below... now that I think
> >
> > about it,
> >
> > > if the numbers aren't in the diesel supplement to your owner's manual,
> >
> > then
> >
> > > the gel point is printed on the back of some of the bottles of fuel
> > > conditioner. Oh, and with the new 6.0L electronically controlled
> >
> > diesel, if
> >
> > > you decide to use a fuel conditioner, "more is NOT better". Raising
> >
> > the
> >
> > > flash point of the fuel too far will play havoc with proper
> >
> > combustion.
> >
> > > We had some initial growing pains with the new 6.0L Diesel, but the
> >
> > reports
> >
> > > I'm seeing lately say that the late 2003 and 2004 units are top
> >
> > drawer.
> >
> > > Dan Bodnar
> > > SV QOL
> > >
> > >
> > > -----Original Message-----From: rhodes22-list-bounces at rhodes22.org
> > > [mailto:rhodes22-list-bounces at rhodes22.org] On Behalf Of Michael
> >
> > Meltzer
> >
> > > Sent: Monday, December 08, 2003 9:46 PM
> > > To: sanderico at earthlink.net; The Rhodes 22 mail list
> > > Subject: Re: [Rhodes22-list] RE: Michael's Diesel #1 and #2
> > >
> > > That nice to know, under a little knowage is dangerous I heard that
> >
> > use
> >
> > > Kerosene can be use up to 20% in the winter, also almost
> > > anything can go into a disel engine, like bio-disel, made from used
> >
> > frechfry
> >
> > > oil :-)
> > >
> > > MJM
> > >
> > > ----- Original Message -----
> > > From: "Rik Sandberg" <sanderico at earthlink.net>
> > > To: <kroposki at innova.net>; "The Rhodes 22 mail list"
> > > <rhodes22-list at rhodes22.org>
> > > Sent: Monday, December 08, 2003 9:54 PM
> > > Subject: Re: [Rhodes22-list] RE: Michael's Diesel #1 and #2
> > >
> > > > Ed,
> > > >
> > > > #1 fuel oil and kerosene are not the same thing. Kerosene is more
> > >
> > > "refined"
> > >
> > > > than #1 oil. #3 fuel oil is an even heavier oil than #2. I think
> >
> > they use
> >
> > > it
> > >
> > > > for firing funaces (like asphalt plants) and things, industrial
> >
> > stuff more
> >
> > > > down south than up around here. It's heavy enough that you have to
> >
> > warm it
> >
> > > up
> > >
> > > > before it will light easily. Not an expert on this though :-)
> > > >
> > > > I did run across a guy from down south a few years ago that claimed
> >
> > to be
> >
> > > > using #3 oil in the truck he was driving. It was about -20 F that
> >
> > night
> >
> > > and I
> > >
> > > > stopped to help him as his truck was froze up (fuel gelled) on the
> >
> > side of
> >
> > > > I-94. Poor bastard was out in that shit in nothing but a light
> >
> > jacket and
> >
> > > a
> > >
> > > > t-shirt. He was, to say the least, happy to see me. I would imagine
> >
> > that
> >
> > > they
> > >
> > > > had to drain whatever fuel was in that truck and start over with all
> >
> > new,
> >
> > > > lighter fuel before that truck would ever go anywhere again before
> >
> > spring.
> >
> > > I
> > >
> > > > think he learned that some of the things you can get away with down
> >
> > south,
> >
> > > > won't get you very far up here when it gets cold. Up here, we've got
> >
> > real
> >
> > > > honest to God.......COLD!!!!!
> > > >
> > > > Rik
> > > >
> > > > On 12/08/2003 08:16 pm, you wrote:
> > > > > KEROSENE! What is # 3 used for? and yes there is a #3. Hey guys
> >
> > help
> >
> > > > > Rummy.
> > > > >
> > > > > Ed K
> > > > >
> > > > >
> > > > >
> > > > > Subject: Re: Michael's Diesel #1 and #2
> > > > >
> > > > >
> > > > >
> > > > > I've always just known it as #1.
> > > > >
> > > > > __________________________________________________
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> >
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